Nuclear localization and antibody specificity. (A-E) COS-7 cells were transfected with ETO, MTGR1, MTG16, AML1-ETO or hSIN3B (A to E respectively). Cells were immobilized, lysed and incubated with α-ETO, α-MTGR1, α-MTG16 or α-SIN3B as described in Materials and Methods. ETO (A I), MTGR1 (B II), MTG16 (C III), AML1-ETO (D I) and hSIN3B (E IV) were localized in the nucleus. (F) Untransfected (Untransf.) cells showed no immunofluroscence (I, II and IV) except for a faint background with α-MTG16 (III). Size bars (10 μM) are shown in panel AI.